U.S. patent application number 16/780181 was filed with the patent office on 2020-06-04 for device for generating a pattern on a clothing for a machine for manufacturing a web material.
The applicant listed for this patent is VOITH PATENT GMBH. Invention is credited to ANDREW ALLUM, ANTONY MORTON, DAVID STUART PONTON, PAUL RAYMOND RIDING.
Application Number | 20200173107 16/780181 |
Document ID | / |
Family ID | 70849075 |
Filed Date | 2020-06-04 |
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United States Patent
Application |
20200173107 |
Kind Code |
A1 |
RIDING; PAUL RAYMOND ; et
al. |
June 4, 2020 |
DEVICE FOR GENERATING A PATTERN ON A CLOTHING FOR A MACHINE FOR
MANUFACTURING A WEB MATERIAL
Abstract
A device for producing a pattern combination on a clothing
includes the following: a rotary screen, a cylindrical jacket
surface with a perforation pattern that defines a first pattern
component. Material in the liquid or pasty state is pressed through
the perforations of the jacket surface of the rotary screen and
deposited on the surface of the clothing in order to produce the
first pattern component on a surface of the clothing, while the
rotary screen, rotating several times about a longitudinal axis
thereof, rolls on the surface of the clothing in at least one path
that continuously revolves on the surface of the clothing at least
once. At least one device produces, synchronously and/or
simultaneously, a second pattern component, which device is
connected indirectly or directly to the rotary screen. The device
for producing the pattern combination also includes a post-run
system.
Inventors: |
RIDING; PAUL RAYMOND;
(BLACKBURN, GB) ; PONTON; DAVID STUART;
(BLACKBURN, GB) ; ALLUM; ANDREW; (DARWEN, GB)
; MORTON; ANTONY; (BEN RHYDDING, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VOITH PATENT GMBH |
HEIDENHEIM |
|
DE |
|
|
Family ID: |
70849075 |
Appl. No.: |
16/780181 |
Filed: |
February 3, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15662481 |
Jul 28, 2017 |
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16780181 |
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14784229 |
Oct 13, 2015 |
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PCT/EP2014/057127 |
Apr 9, 2014 |
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15662481 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D21F 11/006 20130101;
D21F 1/44 20130101; B41F 15/0868 20130101; B41F 15/0836 20130101;
B41M 1/12 20130101 |
International
Class: |
D21F 11/00 20060101
D21F011/00; B41F 15/08 20060101 B41F015/08; D21F 1/44 20060101
D21F001/44 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 10, 2013 |
DE |
102013206273 |
Claims
1. A device for generating a pattern combination on a clothing, the
device comprising: a rotary screen having a longitudinal axis and a
cylindrical sleeve face formed with a perforated pattern
determining a first pattern component; wherein, for generating the
first pattern component on a surface of the clothing, a material in
a liquid or pasty state is squeezed through perforations of the
sleeve face of the rotary screen and is deposited on a surface of
the clothing, while said rotary screen, repeatedly rotating about
said longitudinal axis, rolls at least once over the surface of the
clothing on at least one continuously encircling path on the
surface of the clothing; at least one device indirectly or directly
connected to said rotary screen and configured for synchronously
and/or simultaneously generating a second pattern component; and a
follower system.
2. The device according to claim 1, wherein said at least one
device for simultaneously generating the second pattern component
is at least one pattern ring.
3. The device according to claim 2, wherein said at least one
pattern ring is disposed on an end section of said rotary screen
and fixedly connected to said rotary screen.
4. The device according to claim 2, wherein one pattern ring is
disposed at each end of said rotary screen.
5. The device according to claim 2, which comprises a plurality of
pattern rings.
6. The device according to claim 2, wherein said at least one
pattern ring is formed with at least one surface shape extending
circumferentially on a surface of said pattern ring.
7. The device according to claim 6, wherein said surface shape is a
channel with a shape selected from the group consisting of
straight, curved, undulated, and zigzag.
8. The device according to claim 1, wherein said at least one
device for simultaneously generating the second pattern component
has a pattern identification device by way of which the first
pattern component is detectable.
9. The device according to claim 1, wherein said follower system is
indirectly or directly linked to said at least one device for
simultaneously generating the second pattern component.
10. The device according to claim 9, wherein said at least one
device for simultaneously generating the second pattern component
is at least one pattern ring and a shape of said at least one
pattern ring is mechanically or optically detectable and traceable
by said follower system.
11. The device according to claim 9, which comprises an extrusion
head with one or a plurality of nozzles integrated in said follower
system and configured for deploying the material onto the surface
of the clothing.
12. The device according to claim 11, wherein said follower system
has a controller configured to identify the pattern and to actuate
said extrusion head.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of application
Ser. No. 15/662,481, filed Jul. 28, 2017, which was a continuation
of patent application Ser. No. 14/784,229, which was a .sctn. 371
national stage filing of international application No.
PCT/EP2014/057127, filed Apr. 9, 2014, which designated the United
States; this application also claims the priority, under 35 U.S.C.
.sctn. 119, of German patent application No. DE 10 2013 206 273.7,
filed Apr. 10, 2013; the prior applications are herewith
incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention proceeds from a device and a method for
generating a pattern on a clothing for a machine for manufacturing
a web material, such as, for example, paper, cardboard, tissue, or
a non-woven product, and from a clothing of this type.
[0003] A clothing of this type which may be employed as a forming
wire in a paper machine, for example, is known from European
published patent application EP 1 690 981 A1. In the case of this
known paper machine clothing a pattern from a polymer material is
applied in a screen printing method by means of a rotary screen to
a carrier structure which is configured as a woven fabric, for
example. The pattern having substantially any arbitrary design
embodiment may be applied to the woven carrier fabric so as to thus
generate by way of this pattern a surface structure on one side of
the paper machine clothing manufactured in this way.
[0004] A method for applying a pattern to a paper machine clothing
is known from European published patent application EP 1 690 982
A1, in which method a polymer material forming the pattern is
dispensed in an extrusion operation from an extrusion head and is
thus applied to the surface of a carrier structure which may be of
a woven fabric type, for example. The extrusion head may be
arbitrarily moved above the surface of the carrier structure.
[0005] Furthermore, a clothing for a paper machine, in which a
basic structure is repeatedly printed with a polymer structure is
known from published patent application US 2008/099170 A1, for
example, wherein a first polymer layer has a grid-type structure
and a second polymer layer largely occupies the clearances in the
grid-type first layer and thereby partially superimposes the first
layer.
[0006] U.S. Pat. No. 7,624,765 B2 discloses a woven paper machine
clothing for perfused air drying which has a three-dimensional
woven pattern which has a structure which has height differences in
the direction z of 0.2 mm or more. The clothing has decorative
elements which are surrounded by accentuation areas which are
surrounded by the three-dimensional woven pattern of the clothing
and have a structure which has a lower height than the structure of
the woven pattern. The woven pattern represents a structured
background surface which is the prevailing contact area of the
clothing with the paper web.
[0007] It is particularly disadvantageous in known clothings and
the manufacturing methods thereof here that combinations of
patterns are indeed possible by correspondingly manufacturing and
subsequently printing the basic structure, but that this is very
complex. Multiple printing operations on a structured or
non-structured base structure are also known, as has been mentioned
earlier, but the former have the same disadvantage. In particular
the clothings last mentioned have to be subjected to multiple
processing, causing high manufacturing costs and a high investment
in time.
BRIEF SUMMARY OF THE INVENTION
[0008] It is thus an object of the present invention to state a
method and a device by way of which various patterns may be
simultaneously applied to the surface of a clothing in a simpler
and thus more rapid and more cost-effective way, such that multiple
steps for manufacturing a pattern are not necessary. On account
thereof, processing time may be saved and manufacturing of such
clothings may be designed to be more economical.
[0009] The object in terms of the device is achieved by the device
as claimed, in terms of the method by the method as claimed, and in
terms of the clothing by the clothing as claimed, in each case in
combination with the generic features.
[0010] According to the invention it is provided here that the
device comprises at least one rotary screen, the cylindrical sleeve
face of which has a perforated pattern which determines a first
pattern component and in which, for generating the first pattern
component on a surface of the clothing, a material in a liquid or
pasty state is squeezed through the perforations of the sleeve face
of the rotary screen and is deposited on the surface of the
clothing, while the rotary screen, repeatedly rotating about the
longitudinal axis of the same, rolls over the surface of the
clothing on at least one path which continuously encircles the
surface of the clothing at least once. Furthermore, at least one
means for generating in a synchronous and/or simultaneous manner a
second pattern component is provided, said means being indirectly
or directly connected to the rotary screen. Pattern generation is
regulated by way of a follower system.
[0011] On account of the synchronous and/or simultaneous
application of the two pattern components, very swift and
time-saving manufacturing of the clothing may be performed in just
one operational step. On account of a suitable configuration of the
rotary screen and of the at least one means for generating the
second pattern component, which is connected to said rotary screen,
a large diversity of patterns which are manufacturable in a simple
way and without undesirable misalignments on clothings of arbitrary
widths is available.
[0012] Further advantageous aspects and refinements of the
invention are derived from the dependent claims.
[0013] According to one preferred embodiment of the invention the
at least one means for synchronously and/or simultaneously
generating the second pattern component may be configured in the
form of at least one pattern ring.
[0014] Particularly preferably, the at least one pattern ring may
be disposed on the rotary screen so as to be at the end thereof,
and may be fixedly connected to the rotary screen. On account
thereof, the pattern components are fixedly interconnected,
avoiding misalignments in the pattern.
[0015] According to one aspect of the invention it may be provided
that one pattern ring is present per end of the rotary screen.
[0016] According to one further aspect of the invention it may be
provided that a plurality of pattern rings are present. These may
be provided individually or in pluralities thereof at one or both
of the two ends of the rotary screen.
[0017] At least one surface shape, in particular a channel, may be
advantageously provided in the at least one pattern ring which
surface shape extends circumferentially on a surface of the pattern
ring.
[0018] The channel may preferably have a straight, curved,
undulated, or zigzag shape. On account thereof, corresponding
background patterns may be generated.
[0019] According to one further advantageous embodiment of the
invention, the means for generating the second pattern component
may have a pattern identification device by way of which the first
pattern component is detectable. On account thereof, using an
extrusion unit which is guided in a parallel manner, for example,
the second pattern component may be applied relative to the first
pattern component, this nevertheless being performed in only one
operational step, without the clothing having to pass through a
second separate printing process.
[0020] According to one advantageous aspect of the invention it may
be provided that the follower system is indirectly or directly
linked to the at least one means for synchronously and/or
simultaneously generating the second pattern component.
[0021] Particularly advantageously, the shape of the at least one
pattern ring may be mechanically or optically traceable by the
follower system.
[0022] Particularly preferably, an extrusion head which has one or
a plurality of nozzles by way of which material is deployable onto
the surface of the clothing is integrated in the follower
system.
[0023] According to one advantageous refinement of the invention
the follower system may have a controller by way of which
identification of the pattern and actuation of the extrusion head
is performed.
[0024] It may be advantageously provided that the first pattern
component is composed of a first material, and the second pattern
component is composed of a second material, wherein the first and
the second material are identical to or different from one another.
If and when various requirements are set for the pattern
components, it may be advantageous for one of the materials to be
harder or softer, more resistant to wear, smoother or coarser, than
the other material.
[0025] In the same way, a cross-sectional shape of the first
pattern component, and a cross-sectional shape of the second
pattern component may advantageously be identical to or different
from one another. On account thereof, for example, personalized
motifs may be intensely and clearly highlighted, and may be
surrounded by a background which has been drawn to be softer and
less prominent.
[0026] The material of the pattern components may preferably
contain or be composed of: amide, ester, silicone,
polyurethane.
[0027] Sizing of the second pattern component may advantageously be
at a height of 0 to 10 mm, at a width of 0.1 to 10 mm, and at an
arbitrary length.
[0028] The lines of the second pattern component may be configured
so as to be optionally continuous or discontinuous. On account
thereof, a high degree of flexibility and individualization of the
clothing and of the final product manufactured are enabled.
[0029] The invention will be explained in more detail in an
exemplary manner in the following with reference to the figures and
without limiting the general scope thereof.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0030] FIG. 1 shows a very schematized plan view of a clothing
which has been manufactured by means of the method according to the
invention;
[0031] FIG. 2 shows a very schematized illustration of a rotary
screen for manufacturing a clothing having two patterns;
[0032] FIG. 3 shows a schematic perspective illustration of a
pattern ring for use in a device according to the invention;
and
[0033] FIG. 4 is a schematic perspective illustration of an
application of the device for printing a clothing web.
DESCRIPTION OF THE INVENTION
[0034] A plan view of a clothing 1 which is particularly suitable
for use in a machine for manufacturing a fibrous web, such as in a
paper, cardboard, or tissue machine, as well as in a machine for
manufacturing a non-woven product, is illustrated in a very
schematized view in FIG. 1.
[0035] A plurality of clothings 1 which depending on their position
fulfill various tasks are currently provided in such a machine. For
instance, a clothing 1 in the forming section serves as a forming
wire and thus for initially de-watering the fibrous suspension
which has been sprayed onto the forming wire or has been injected
between two forming wires in a double-wire former, and for
orienting the fibers in the nascent fibrous web. Clothings 1 are
provided as pressing felts for further de-watering in the
downstream pressing section, which clothings 1 should have a high
absorptive capacity for water, good resilience, smooth contact
faces to the fibrous web, and a low tendency toward rewetting. The
clothing 1 in the drying section is often configured as a drying
wire in the shape of a helical structure and is distinguished by a
high resistance to temperature at high permeability to vapor.
[0036] Clothings 1 also often serve for incorporating a decorative
pattern into the fibrous web, this representing the current
standard in the field of hygiene tissues in particular. The
patterns here have both aesthetic features as well as features
which influence the properties of the paper web, such as the grip
of the surface, the thickness of the layers, etc.
[0037] The individual features here are often conceived such that a
decorative and often also personalized pattern is desirable, but
that the latter is not able to fulfill the requirements which are
set for the physical properties of the fibrous web. It has thus
been necessary to date for the clothing 1 to be subjected to at
least two separate operational steps in order for at least two
patterns to be manufactured in or on the respective clothing. For
example, as mentioned at the outset, it is possible for a
three-dimensional structure to be generated when manufacturing the
basic structure 2 of the clothing 1, and for this structure to be
then superimposed by a pattern which is printed on at least one
surface of the clothing 1, for example. The structure of the basic
structure here may be manufactured by established weaving patterns,
while the printed pattern is applied by a screen printing method,
for example. Weaving of such basic structures is in particular a
very complex process which moreover is very limited in terms of its
diversity of patterns. Due to the nature of weaving, in each case
only the machine direction, the machine cross direction, and
diagonals may be incorporated into the pattern; an arbitrary
selection of patterns is impossible.
[0038] Multiple printing, for example by screen printing, and
subsequent printing by means of an extrusion nozzle device, are
also known and possible. However, depending on the sizing thereof,
it may take very long and/or be highly cost-intensive for a
clothing 1 to be manufactured by means of such multi-stage
methods.
[0039] According to the invention, it is therefore proposed that
two pattern groups A and B are applied to the clothing 1
synchronously and/or simultaneously, using only one device, such
that a regular or irregular pattern results from two different
components, having a personalized motif and a background structure
surrounding the motif, without complex weaving processes or a
plurality of printing steps being necessary. Arbitrary planar
structures such a woven fabrics, cross-laid structures, warp-knits,
helical wires, helically coiled structures, and also films may be
printable as a basic structure
[0040] A personalized pattern component A, which is represented by
the faces, is configured in front of a background of line-shaped
structures which in the exemplary embodiment form a zigzag pattern
B, and is shown in FIG. 1. Both pattern components A and B are
composed of a material such as, for example, amides, polyurethane,
silicone, esters, or other suitable materials which are capable of
processing by printing or extruding, which material is dispensed
from correspondingly designed extrusion devices onto the basic
substrate of the clothing 1. The pattern component A here may be
composed of the same material as the pattern component B, or of a
material which is different therefrom. Selection of the materials
may be performed according to the requirements pertaining to
stability, sizing, smoothness, elasticity, gas and water
permeability, etc., of the individual pattern components.
[0041] It is possible for arbitrary pattern components A and B to
be combined, for example for personalized pattern components A,
such as company logos, lettering, pictorial representations of
arbitrary objects, etc., to be combined with pattern components B
of straight lines, undulated lines, zigzag lines, interrupted
lines, or dots. Here, in a method which will be described in more
detail below, application of material of the pattern components A
and B is precisely controlled, such that the personalized motif A
is framed by the background pattern B.
[0042] The basic substrate may be available in the form of an
endless belt or as a planar structure. Said basic substrate has to
be correspondingly held or clamped by a suitable device, in order
for the patterns A and B to be able to be applied to the former. If
and when the basic substrate is available in the form of an endless
belt, for example, it may be held and clamped by a combination of
two or more rollers. The rollers may be rotatably mounted and be
provided with a drive.
[0043] Application of the pattern components A and B is performed
according to one preferred embodiment of the invention, using a
rotary screen 2 which is illustrated in a very schematized manner
in FIG. 2. Rotary screens 2 of this type are already known from the
prior art. Said rotary screens here are drum-shaped formations, for
example from a thin sheet metal into which the pattern component A
is incorporated in a suitable way, for example by punching or laser
processing. The rotary screen 2 rolls on the basic substrate and
thereby deploys material through the openings onto the surface of
the basic substrate. If and when the basic substrate is
substantially wider than the width of the rotary screen 2, the
rotary screen 2 may be guided for a plurality of revolutions in a
helical track in a transverse manner across the entire surface of
the basic substrate. Sizing of the rotary screen 2 and a suitable
controller system ensure that the pattern component A thus
manufactured is free from misalignments and overlaps.
[0044] The second pattern component B, or the background pattern,
in the exemplary embodiment is applied to the basic substrate using
a guide system having pattern rings 3. The latter are disposed on
the rotary screen 2 so as to be at the end thereof. A pattern ring
3 may be disposed only at one end of the rotary screen 2, however,
in each case at least one pattern ring 3 may be provided on each
end; a plurality of pattern rings 3 per end may also be combined.
This at least one pattern ring 3 has the characteristic shape of
the background pattern B, as may be seen in FIG. 3. In the present
exemplary embodiment the line-based geometry is determined by a
channel 4 in the pattern ring 3. The channel 4 may be incorporated
into the pattern ring 3 by milling or laser processing, for
example.
[0045] The material for generating the background pattern B is
supplied to the at least one pattern ring 3 by a suitable supply
system and is deposited on the basic structure.
[0046] One of the great advantages of this assembly lies in that
the pattern-generating structures for the motif A and the
background B are fixedly interconnected. This permits a high degree
of controlled precision during application of the pattern and also
allows for complex combinations. Consequently, the motif A and the
background B are always mutually disposed and delimited in an
accurate manner; the motif A is cleanly framed by the background B,
and the patterns A and B do not mutually overlap on account of
undesirable and unintentional misalignments when the material is
being applied.
[0047] A suitable controller system may be used in order to
automatically prompt the start and the end of the background
pattern B, such that clean separation of the motif A and the
background B is ensured. Optionally, it is of course also possible
for the motif A and the background B to be mutually contacting,
intersecting, or superimposing, if required, depending on which
properties are desired with a view to the design and the technical
requirements of the pattern components A and B.
[0048] The geometry of the background B and the disposal of the
same are determined by the pattern rings 3. A follower system,
which may be mechanically or optically operated, may be used for
tracking the shape of the at least one pattern ring 3, for example
the channel 4. An extrusion head, which may have one or a plurality
of nozzles, is integrated in the follower system and is actuated by
suitable controller means such that application of the material in
each case starts and ends at the desired point.
[0049] In order for the motifs A to be exposed, the one nozzle or
the plurality of nozzles of the extrusion head may be activated or
deactivated, so as to allow or restrict the dispensing of material.
This is synchronized with the position of the motif A in the rotary
screen 2.
[0050] The completed clothing 1, after having been completely
printed, contains a simultaneously manufactured pattern composed of
the components A and B.
[0051] Typical sizings of the pattern component B may be selected
as is described in the following: [0052] Height: 0 mm (in this case
the pattern B does not stand proud of the surface of the basic
substrate but completely sinks thereinto) up to 10 mm [0053] Width:
0.1 mm to 10 mm [0054] Length: arbitrary combinations of line
lengths (from very short or punctiform, respectively, up to very
long or continuous, respectively) across the circumferential length
of the basic substrate are conceivable and possible (in the case of
an endless belt). The lines may be continuous if no large-scale
motif A is envisaged. The end result thus may be any combination of
continuous and discontinuous lines B, and regions with and without
a motif A.
[0055] Controlling the start and end of the background pattern B
may be performed pneumatically, hydraulically, electrically, for
example, or may comprise a suitable combination of the previously
mentioned possibilities.
[0056] It would be also conceivable and possible for an image
recognition device which is indirectly or directly connected to the
rotary screen 2 to be provided as a means for generating the second
pattern component B, which software-supported image recognition
device recognizes the pattern component A, and by way of suitable
linking to the follower system controls the application of the
pattern component B. Recognition here may be performed by way of
optical or mechanical sensors, for example tactile sensors.
[0057] Suitable actuation and linking must then be provided between
the rotary screen 2, the image recognition device, and the follower
system. The image recognition device may furthermore also be an
integral component part of the follower system.
[0058] FIG. 4 shows an exemplary embodiment of a device according
to one aspect of the current invention. A fabric 1, which may be a
woven wire or a felt, moves in the direction D as indicated by the
arrow. Here, a rotary screen 2 is used to apply a pattern A to the
fabric 1. The pattern A illustrated here is a circular pattern.
Here, a multitude of patterns can be provided, for example
personalized patterns such a company logos letterings or pictorial
representations of arbitrary objects. The generation of this
pattern A is a screen printing process, where a material in liquid
or pasty state is squeezed through perforations in the rotary
screen. The material is usually a polymer material and may be
chosen from the group of amides, polyurethane, silicone, esters,
and other suitable materials.
[0059] The device further comprises a follower system 10. The
follower system 10 also has a plurality of extrusion nozzles 11.
These extrusion nozzles 11 are attached to a holder 12, usually a
bar 12. The are disposed at a fixed distance. The extrusion nozzles
are suited to generate a pattern B on the fabric. This pattern B is
generated by nozzle extrusion of a material onto the fabric. The
material for generating pattern B may be the same material as that
for pattern A. It may also be a different material, but is usually
also chosen from the group of amides, polyurethane, silicone, or
esters.
[0060] In contrast to pattern A, which is due to the screen
printing technology, preferably a set of discrete pattern elements,
pattern B illustrated in FIG. 4 is a line shape pattern. By moving
the extrusion nozzles 11, or the entire holder 12 in cross machine
direction (CMD), the lines of pattern B may take the form of
undulating lines or zigzag lines.
[0061] The patterns A and B are synchronized so as, for example, to
avoid an unwanted superposition of the patterns. In order to
realize the synchronization of pattern A and pattern B--for example
to avoid an unwanted superimposing of these two patterns--a pattern
ring 3 may be provided on at least one side of the rotary screen 2.
The synchronization may be achieved by providing a channel 4 or
groove 4 in the pattern ring 3. The connector bar 13 that connects
the follower system 10 with the rotary screen 2 may be guided by
this channel 4 or groove 4.
[0062] The channel 4 may for example have an undulating shape. By
the rotation of the rotary screen 2, the undulation of the channel
4 forces the connector 13 and therefore also the follower system 10
to move back and forth in cross machine direction. So, the
extrusion nozzles 11 deposit a pattern B in the form of undulating
or zigzag-ing lines on the fabric.
[0063] By a suitably shaping the channel 4 in the pattern ring 3 it
can be achieved that the patterns A and B remain in the desired
relation to each other. The pattern ring 3 and the rotary screen 2,
i.e., the applicator for the first pattern A, have a fixed
structural relationship. Accordingly, the patterns A and B also
have a fixed structural relationship.
[0064] While the use of a pattern ring 3 as described is a very
easy and beneficial way to ensure the desired synchronization,
other ways are also possible. For example, pattern rings 3 can be
provided on both sides of the rotary screen 12.
[0065] Alternatively, the connection between the follower system 10
and the rotary screen 2 does not have to be a mechanical
connection. It is also possible to use an optical system like a
camera system. In such an embodiment, a camera would detect a
pattern--may e.g. be the pattern A directly or some markings on the
rotary screen--and initiate a cross directional movement of the
follower system 10 based on this image information.
[0066] The invention is not limited to the illustrated exemplary
embodiments. Combinations of the features in particular are
possible and conceivable.
* * * * *